This invention relates to the processing of metallic salts of charge transfer agents as well as devices formed by such methods. In particular, techniques for processing metal-tetracyanoquinodimethane (TCNQ) salts, metal-tetracyanonaphthoquinodimethane (TNAP) salts, metal-tetracyanoethylene (TCNE) salts, dichlorodicyanobenzoquine (DDQ) salts and similar metallorganic semiconductor salts are disclosed to form resists, active electronic devices and image-storage devices, and to dope substrates and modify the bulk or surface properties of materials.
Organic electron-acceptors and their metallic salts have been studied by numerous researchers. Cuprous and other metallic salts of TCNQ, for example, were disclosed by Melby et al. in "Substituted Quinodimethanes II. Anionradical Derivatives and Complexes of 7,7,8,8 Tetracyanoquinodimethane," Vol. 84, J. of American Chemistry, pp. 3374-3387 (1962). The electrical switching properties of Cu-TCNQ films were disclosed by Potember et al. in article "Electrical Switching and Memory Phenomena in Cu-TCNQ Thin Films," Vol. 34, Applied Physics Letters, pp. 405-407 (1979) and further described by the present inventors and a colleague in an article "Raman study of the Mechanism of Electrical Switching in Cu-TCNQ Films," Vol. 42, Solid State Communications, pp. 561-565 (1982). The optical properties of such films were disclosed by the present inventors in an article "Optically Induced Transformations of Metal TCNQ Materials," Vol. 45, Solid State Communications, pp. 165-169 (1983). The teachings of the above referenced articles are incorporated herein by reference.
Despite the teachings in this art, few commercial applications of metallic-TCNQ salts and the like have been found to date. In the field of semiconductor processing, for example, there currently is a significant need for resist materials that can be patterned and developed to yield sub-micron structures for active electronic devices. Similarly, there is a need for better memory materials for both reversible and "read-only" information storage devices. High resolution image storage is yet another area where imaging materials of high quality would satisfy a substantial need.